Microbe Thrives On Arsenic

Five years ago, the U.S. Geological Survey's Ronald S. Oremland discovered a microbe that can generate energy from arsenic. Now, Oremland has helped a team led by Felisa Wolfe-Simon of the NASA Astrobiology Institute uncover a bacterium that can grow in the presence of either arsenic or phosphorus (Science, DOI: 10.1126/science.1197258).

Living things are largely made of six elements: carbon, nitrogen, hydrogen, oxygen, sulfur, and phosphorus. But some scientists searching for life on . . .